Apparatus for uniting wax coated paper



. y 1941- H. E. HALLMAN 2,249,470

APPARATUS FOR UNITING WAX COATED PAPER Filed Aug. 27. 1938 MINA;

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F1 INVENTOR.

9 Jl'arold .JCaZImafl W m/e m iew ATTORNEYS Patented July 15, 194 1 UNITED STATES PATENT OFFICE APPABATUSFOgiITiZG WAX COATED Harold a. Hellman, Catonsville, Md. Application August 21, ms, Serial No. 227,111

'IClalms.

My invention relates to a novel apparatus for the high speed sealing of bag bottoms and more specifically my invention relates to an apparatus for sealing wax coated paper carrying a deposited adhesive without the employment'of pressure.

In the manufacture of bags and similar articles from wax coated paper, the formation of a strongly sealed bag bottom has, presented many difflculties. When it is attempted to merely heat seal the wax coated paper to obtain a wax to wax engagement, the bottom so formed has insufllcient strength. When glue is employed to strengthen the bond, the glue fails to strike through the wax coating and hence has insufficient grasp upon the paper.

Certain apparatuses have been devised for eifecting the penetration of the glue through the wax coating by the application of heat to that area without pressure, but such apparatuses have insuflicierit speed for the high speed operations required in the manufacture of these bags.

' .wax coated paper.

I have devised a novel apparatus whereby after i the bag bottoms are folded they are delivered to a drum and carried onthe drum by gripper mechanisms. On the drum they are subjected to heat from an exposed radiant heater in such a manner that the bag bottom and particularly the area which is to be heated to allow the penetration of the glue through the wax coating is subjected to an intense penetration oi'heat through an enclosed chamber for a short period of time. Be-

cause of the high heat developed in the closed chamber, only a short period of heating is required and my apparatus thus makes possible the rapid movement of the bags during this bottom sealing operation. I 1

To achieve this intense short period heating effect I mount adjacent to the large drum on which the bags are carried an auxiliary roll which has one or more out out sections, which sections carry an exposed radiant heater. An example of.

such a heater is a porcelain core with an electric wire wound around it, which wire constitutes a resistance heater. The movement of the cut out roll is synchronized so that the cut out section fits over and encloses the bag bottom as the bag bottom passes in its path on the large drum. i Two or more such cut out rolls may be mounted adjacent the large drum if further or an extended heating of the bottom is desired to effect such a melting of the wax as is necessary to allow the glue to strike through the wax to the fibres oi the paper itself.

' In themanufacture of bags from wax coated paper speed is one of the most important r quimaterial from which my sites. My apparatus, comprising a large drum carrying the folded bags with the heating rolls mounted adjacent thereto so that an intense heat is focused upon the bottom of the bag to melt the wax thereon, makes possible this desirwithin a chamber focusing the heat directly on the areas to be heated is extremely effective for the short period of time in which it operates upon the wax coated paper in this high speed apparatus.

Although I refer bags are manufactured, it is to be understood that I use this by way of example only and that the apparatus and methods of myinvention are directed to the use of any heat sensitive material generally, and particularly sheet materials coated with heat sensitive materials, such as thermo-plastics as for example cellulose derivatives and vinyl compounds,

synthetic resins and rubber derivatives and synthetic rubber compounds.

It is the object of my invention to provide an apparatus for effecting the rapid sealing of wax coated paper.

It is another object of my invention to provide an apparatus which throws concentrated heat on to a small area of wax coated paper to melt the wax thereon.

It is a further object of my invention to provide an apparatus which throws concentrated radiated heat on to a specific area of wax coated paper to melt the wax thereon. a

It is a further object of my invention to effect an adhesive bond with a paper to paper engage-' ment by employing heat without pressure in a high speed operation.

It is a further object of my invention to provide an apparatus for effecting an adhesive bond in wax coated paper which comprises carrying a drum an d an adjacently mounted roll with an exposed radiant heater; carried in the cut out section.

It is a further objectof my invention to apply to wax coated paper as the i heat to a bag bottom without interrupting its movement, the bag bottom'being substantially enclosed with respect to the heating means.

These and other objects of my invention will become apparent from the description which follows.

In the drawing, 7

Figure 1 represents a side. elevation of the'apparatus of my invention.

Figure 2 is a cross-section taken along the line 2-2 of Figure 1. 1

Figure 3 is a perspective of the bag of my in vention.

Figure 4 is a cross-section taken along the line 4-4 of Figure 3 with the relative position of the apparatus shown in dotted lines.

Referring now more specifically to the drawing, in Figure 1 is shown the tapes i and 2 which travel over the bag 3 which in combination with the tape I hold it in its path of travel in the direction indicated by the arrows. Tapes I and 2 are trained aboutroll 5 and the tape 4 is trained about the roll 6. The undertape 4 terminates its path of travel with respect to the bags at the roll 6 and the gripper 9, mounted on the drum l0 grasps the bag at that point and draws it from between the tapes I and 2. A plurality of grippers 5, ii and i2 are adapted to pick bags thus conveyed by the tapes. The grippers hold the bags on to the drum l0 and convey them on the path of the drum 10 indicated by the arrows. The-grippers grasp the bottom of the bag and hold it with the folded over portion up. Mounted adjacent to the drum I0 is a roll [5 which rotates on a shaft ii. In a cut out portion ll of the roll I5 is positioned a heater ll of the exposed radiant type. The movement of the roll I! is so timed that the cut away portion always is placed over the folded over end of the bag as shown in Figure 4 so that the bottoms of the bags are subjected to radiant heat thrown 01! by the exposed radiant heater It. The roll I! is similar to the roll I5 and exercises the same function, being used to give added heat so that the wax coating can be sufiiciently melted to allow the glue to strike through the wax to the paper.

The timing of the movement of rolls I! and I! with respect to the movement of roll ll may be obtained in any suitable manner. Thus for instance a gear 40 mounted on the shaft ll of .roll I0 may engage gears 42 and 42' respectively mounted on the shafts i6 and I! of rolls I! and I 5.

The diameters of gears Ill, 42 and 41' may obviously be so arranged as to bring the radiant heater into position abutting the surface of the drum at the specific intervals when the heat is to be applied to the bags. If necessary to secure a specific direction of rotation of drums I! and I! with respect to the drum ll, additional gears may be inserted between gears ll, 42 and 42'.

After the bags 3 have been treated on this apratus they are carried down to the conveyor belt 23 which revolves about the roll 24 in the direction indicated by the arrows. The bags are thus carried away from the apparatus.

In Figure 2 is shown in detail the heater in the cut out section with respect to the bag bottom. It is noted that the gripper H grasps the bag bottom in'the center and carries it below the exposed radiant heater II which comprises wire 28 wrapped around a suitable insulating rod 29. The coil heater is supported by the brackets 30 and 3| which are secured to the frame by the fastening means :2 and a. Wire :0 travels 75 the through the roll to the coil through the channels 3! and 36.

In-Flgure 3 the bag 3 is shown with the folded over bottom It beneath which lies the glue line ll shown in dotted lines. This glue is placed onto the wax coated paper and the radiant heat thrown on to it effects the melting of the wax coating allowing the glue II to strike through the wax to the paper to firmly secure the same. The longitudinal seam of the bag is indicated at 43.

Figure 4. shows in detail the relation of the heater l8 to the bag bottom I and the glue line ll Therein can be seen the manner in which the cut out section I I of the roll [5 completely encloses the bag bottom in its travel and throws a radiant heat thereon .to effect a concentrated heating of the wax coated paper. The benefits of radiant heating have been set forth previously in the specification. Depending on the consistency of the wax at its melting point and also on the speed of the travel of the bag a multiplicity of such heating units such as l5 and I! may be employed. I

The present invention employs heat without pressure by such means that a high speed operation of bag forming is employed. The concentrated enclosed radiant heating effect provides new and unexpected results in obtaining rapid melting, particularly of the inner wax coating as is desired. Because no pressure is employed there is no tendency to spread out the glue for deleterious results.

The arrangement of the drum carrying the bags and the adjacently mounted rotating rolls with the cut out sections containing the exposed radiant heaters provides for the application of heat to the bags without slowing down the operation. Because the exposed radiant type of heat is used and an enclosed chamber formed when heat is. applied sufficient heat is imparted to the bag bottoms for the desired melting action.

Although I have set forth a particular apparatus for carrying out my invention, it is within the scope of my invention to utilize obvious alternatives. Thus, other means may be employed for conveying the bags to and from the drum. Further, modifications of the drum and heater rolls may be employed.

Of particular importance to my invention is the provision for substantially enclosed bag bottoms during the heating operation, and also the heating means employed is of importance.

I have set forth the above described apparatus by way of illustration and I intend that my invention be limited only by the appended claims.

I claim:

1. An apparatus for sealing bags made from wax coated paper which comprises a. drum, means mounted on the drum for holding the bags, a roll mounted adjacent said drum, said roll having a cut-away section, an exposed radiant heater located within said cut-away section, driving means between said roll and said drum adapted to move said roll and said drum in synchronous movement so that the cut-away section of said roll is positioned over that portion of the bag to be sealed.

1 2. An apparatus for sealing bag bottoms made from wax coated paper carrying an adhesive which comprises a drum, in roll mounted adjacent said drum, said roll having a cut-away section. an exposed radiant heater located within said cut-away section, said heater being spaced from peripheral surface of said roll, driving means between said roll and said drum adapted to move said roll and said drum in synchronous movement so' that the cut-away section of said roll is positioned over the bag bottom of the bag carried by said drum.

3. An apparatus for sealing bag bottoms made from wax .coated paper carrying an adhesive which comprises a drum, gripper means mounted on the drum for holding the bag bottoms to be sealed, a roll mounted adjacent said drum, said roll having at least one cut-away section, an ex posed radiant heater located within said cut-away section, said heater being spaced from the peripheral surface of said roll, driving means between said roll and said drum adapted to move said roll and saiddrum in synchronous movement so that the cut-away section of said roll is positioned over the bag bottomrof the bag held by the gripping means on said drum.

4. An apparatus forsealing bag bottoms made from wax coated paper carrying an adhesive which comprises a drum, gripper means mounted on the drum for holding the bag bottoms to be sealed, a roll mounted adjacent said drum, said" roll having at least one cut-away section, an exposed radiant heater located within said cutmounted on the drum for holding the bag bottoms to be sealed, a plurality of rolls mounted adjacent said drum, each roll having at least onecutaway portion in its surf-ace, an exposed radiant heater located within said cut-away portion, the rotary movement of said drum and said adjacently positioned rolls being so timed that the cut-away sections of said rolls carrying the heaters contact the bag bottoms and enclose said bag bottoms to subject them to intense heat.

6. A high speed bag bottom sealing apparatus comprising a drum, gripper means on said drum for gripping bag bottoms, means for delivering bags to said gripper means, an exposed radiant heater positioned in recessed members, said rece ssed members moving adjacent to said drum and in close contact with said bag bottoms.

f7. An apparatus for sealing bags made from wax coated paper which comprises a drum, means mounted on the drum for holding the bags, a ro tating member mounted adjacent said drum, said rotating member carrying an exposed radiant heater, means carriedby said rotating member for directing heat from said exposed radiant heatfor directing mounted on said rotating member.

HAROLD E. HALLMAN. 

